src/icmp/Icmp6.cc

   1 /*
   2  * Copyright (C) 1996-2014 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 /* DEBUG: section 42    ICMP Pinger program */
  10
  11 //#define SQUID_HELPER 1
  12
  13 #include "squid.h"
  14
  15 #if USE_ICMP
  16
  17 #include "Debug.h"
  18 #include "Icmp6.h"
  19 #include "IcmpPinger.h"
  20 #include "leakcheck.h"
  21 #include "SquidTime.h"
  22
  23 // Some system headers are only neeed internally here.
  24 // They should not be included via the header.
  25
  26 #if HAVE_NETINET_IP6_H
  27 #include <netinet/ip6.h>
  28 #endif
  29
  30 // Icmp6 OP-Codes
  31 // see http://www.iana.org/assignments/icmpv6-parameters
  32 // NP: LowPktStr is for codes 0-127
  33 static const char *icmp6LowPktStr[] = {
  34     "ICMP 0",                   // 0
  35     "Destination Unreachable",  // 1 - RFC2463
  36     "Packet Too Big",           // 2 - RFC2463
  37     "Time Exceeded",            // 3 - RFC2463
  38     "Parameter Problem",                // 4 - RFC2463
  39     "ICMP 5",                   // 5
  40     "ICMP 6",                   // 6
  41     "ICMP 7",                   // 7
  42     "ICMP 8",                   // 8
  43     "ICMP 9",                   // 9
  44     "ICMP 10"                   // 10
  45 };
  46
  47 // NP: HighPktStr is for codes 128-255
  48 static const char *icmp6HighPktStr[] = {
  49     "Echo Request",                                     // 128 - RFC2463
  50     "Echo Reply",                                       // 129 - RFC2463
  51     "Multicast Listener Query",                 // 130 - RFC2710
  52     "Multicast Listener Report",                        // 131 - RFC2710
  53     "Multicast Listener Done",                  // 132 - RFC2710
  54     "Router Solicitation",                              // 133 - RFC4861
  55     "Router Advertisement",                             // 134 - RFC4861
  56     "Neighbor Solicitation",                    // 135 - RFC4861
  57     "Neighbor Advertisement",                   // 136 - RFC4861
  58     "Redirect Message",                         // 137 - RFC4861
  59     "Router Renumbering",                               // 138 - Crawford
  60     "ICMP Node Information Query",                      // 139 - RFC4620
  61     "ICMP Node Information Response",           // 140 - RFC4620
  62     "Inverse Neighbor Discovery Solicitation",  // 141 - RFC3122
  63     "Inverse Neighbor Discovery Advertisement", // 142 - RFC3122
  64     "Version 2 Multicast Listener Report",              // 143 - RFC3810
  65     "Home Agent Address Discovery Request",             // 144 - RFC3775
  66     "Home Agent Address Discovery Reply",               // 145 - RFC3775
  67     "Mobile Prefix Solicitation",                       // 146 - RFC3775
  68     "Mobile Prefix Advertisement",                      // 147 - RFC3775
  69     "Certification Path Solicitation",          // 148 - RFC3971
  70     "Certification Path Advertisement",         // 149 - RFC3971
  71     "ICMP Experimental (150)",                  // 150 - RFC4065
  72     "Multicast Router Advertisement",           // 151 - RFC4286
  73     "Multicast Router Solicitation",            // 152 - RFC4286
  74     "Multicast Router Termination",                     // 153 - [RFC4286]
  75     "ICMP 154",
  76     "ICMP 155",
  77     "ICMP 156",
  78     "ICMP 157",
  79     "ICMP 158",
  80     "ICMP 159",
  81     "ICMP 160"
  82 };
  83
  84 Icmp6::Icmp6() : Icmp()
  85 {
  86     ; // nothing new.
  87 }
  88
  89 Icmp6::~Icmp6()
  90 {
  91     Close();
  92 }
  93
  94 int
  95 Icmp6::Open(void)
  96 {
  97     icmp_sock = socket(PF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
  98
  99     if (icmp_sock < 0) {
 100         debugs(50, DBG_CRITICAL, HERE << " icmp_sock: " << xstrerror());
 101         return -1;
 102     }
 103
 104     icmp_ident = getpid() & 0xffff;
 105     debugs(42, DBG_IMPORTANT, "pinger: ICMPv6 socket opened");
 106
 107     return icmp_sock;
 108 }
 109
 110 /**
 111  * Generates an RFC 4443 Icmp6 ECHO Packet and sends into the network.
 112  */
 113 void
 114 Icmp6::SendEcho(Ip::Address &to, int opcode, const char *payload, int len)
 115 {
 116     int x;
 117     LOCAL_ARRAY(char, pkt, MAX_PKT6_SZ);
 118     struct icmp6_hdr *icmp = NULL;
 119     icmpEchoData *echo = NULL;
 120     struct addrinfo *S = NULL;
 121     size_t icmp6_pktsize = 0;
 122
 123     memset(pkt, '\0', MAX_PKT6_SZ);
 124     icmp = (struct icmp6_hdr *)pkt;
 125
 126     /*
 127      * cevans - beware signed/unsigned issues in untrusted data from
 128      * the network!!
 129      */
 130     if (len < 0) {
 131         len = 0;
 132     }
 133
 134     // Construct Icmp6 ECHO header
 135     icmp->icmp6_type = ICMP6_ECHO_REQUEST;
 136     icmp->icmp6_code = 0;
 137     icmp->icmp6_cksum = 0;
 138     icmp->icmp6_id = icmp_ident;
 139     icmp->icmp6_seq = (unsigned short) icmp_pkts_sent;
 140     ++icmp_pkts_sent;
 141
 142     icmp6_pktsize = sizeof(struct icmp6_hdr);
 143
 144     // Fill Icmp6 ECHO data content
 145     echo = (icmpEchoData *) (pkt + sizeof(icmp6_hdr));
 146     echo->opcode = (unsigned char) opcode;
 147     memcpy(&echo->tv, &current_time, sizeof(struct timeval));
 148
 149     icmp6_pktsize += sizeof(struct timeval) + sizeof(char);
 150
 151     if (payload) {
 152         if (len > MAX_PAYLOAD)
 153             len = MAX_PAYLOAD;
 154
 155         memcpy(echo->payload, payload, len);
 156
 157         icmp6_pktsize += len;
 158     }
 159
 160     icmp->icmp6_cksum = CheckSum((unsigned short *) icmp, icmp6_pktsize);
 161
 162     to.getAddrInfo(S);
 163     ((sockaddr_in6*)S->ai_addr)->sin6_port = 0;
 164
 165     assert(icmp6_pktsize <= MAX_PKT6_SZ);
 166
 167     debugs(42, 5, HERE << "Send Icmp6 packet to " << to << ".");
 168
 169     x = sendto(icmp_sock,
 170                (const void *) pkt,
 171                icmp6_pktsize,
 172                0,
 173                S->ai_addr,
 174                S->ai_addrlen);
 175
 176     if (x < 0) {
 177         debugs(42, DBG_IMPORTANT, HERE << "Error sending to ICMPv6 packet to " << to << ". ERR: " << xstrerror());
 178     }
 179     debugs(42,9, HERE << "x=" << x);
 180
 181     Log(to, 0, NULL, 0, 0);
 182     Ip::Address::FreeAddrInfo(S);
 183 }
 184
 185 /**
 186  * Reads an RFC 4443 Icmp6 ECHO-REPLY Packet from the network.
 187  */
 188 void
 189 Icmp6::Recv(void)
 190 {
 191     int n;
 192     struct addrinfo *from = NULL;
 193 //    struct ip6_hdr *ip = NULL;
 194     static char *pkt = NULL;
 195     struct icmp6_hdr *icmp6header = NULL;
 196     icmpEchoData *echo = NULL;
 197     struct timeval now;
 198     static pingerReplyData preply;
 199
 200     if (icmp_sock < 0) {
 201         debugs(42, DBG_CRITICAL, HERE << "dropping ICMPv6 read. No socket!?");
 202         return;
 203     }
 204
 205     if (pkt == NULL) {
 206         pkt = (char *)xmalloc(MAX_PKT6_SZ);
 207     }
 208
 209     Ip::Address::InitAddrInfo(from);
 210
 211     n = recvfrom(icmp_sock,
 212                  (void *)pkt,
 213                  MAX_PKT6_SZ,
 214                  0,
 215                  from->ai_addr,
 216                  &from->ai_addrlen);
 217
 218     preply.from = *from;
 219
 220 #if GETTIMEOFDAY_NO_TZP
 221
 222     gettimeofday(&now);
 223
 224 #else
 225
 226     gettimeofday(&now, NULL);
 227
 228 #endif
 229
 230     debugs(42, 8, HERE << n << " bytes from " << preply.from);
 231
 232 // FIXME INET6 : The IPv6 Header (ip6_hdr) is not availble directly >:-(
 233 //
 234 // TTL still has to come from the IP header somewhere.
 235 //      still need to strip and process it properly.
 236 //      probably have to rely on RTT as given by timestamp in data sent and current.
 237     /* IPv6 Header Structures (linux)
 238     struct ip6_hdr
 239
 240     // fields (via simple define)
 241     #define ip6_vfc             // N.A
 242     #define ip6_flow    // N/A
 243     #define ip6_plen    // payload length.
 244     #define ip6_nxt             // expect to be type 0x3a - ICMPv6
 245     #define ip6_hlim    // MAX hops  (always 64, but no guarantee)
 246     #define ip6_hops    // HOPS!!!  (can it be true??)
 247
 248         ip = (struct ip6_hdr *) pkt;
 249         pkt += sizeof(ip6_hdr);
 250
 251     debugs(42, DBG_CRITICAL, HERE << "ip6_nxt=" << ip->ip6_nxt <<
 252                 ", ip6_plen=" << ip->ip6_plen <<
 253                 ", ip6_hlim=" << ip->ip6_hlim <<
 254                 ", ip6_hops=" << ip->ip6_hops   <<
 255                 " ::: 40 == sizef(ip6_hdr) == " << sizeof(ip6_hdr)
 256     );
 257     */
 258
 259     icmp6header = (struct icmp6_hdr *) pkt;
 260     pkt += sizeof(icmp6_hdr);
 261
 262     if (icmp6header->icmp6_type != ICMP6_ECHO_REPLY) {
 263
 264         switch (icmp6header->icmp6_type) {
 265         case 134:
 266         case 135:
 267         case 136:
 268             /* ignore Router/Neighbour Advertisements */
 269             break;
 270
 271         default:
 272             debugs(42, 8, HERE << preply.from << " said: " << icmp6header->icmp6_type << "/" << (int)icmp6header->icmp6_code << " " <<
 273                    ( icmp6header->icmp6_type&0x80 ? icmp6HighPktStr[(int)(icmp6header->icmp6_type&0x7f)] : icmp6LowPktStr[(int)(icmp6header->icmp6_type&0x7f)] )
 274                   );
 275         }
 276         Ip::Address::FreeAddrInfo(from);
 277         return;
 278     }
 279
 280     if (icmp6header->icmp6_id != icmp_ident) {
 281         debugs(42, 8, HERE << "dropping Icmp6 read. IDENT check failed. ident=='" << icmp_ident << "'=='" << icmp6header->icmp6_id << "'");
 282         Ip::Address::FreeAddrInfo(from);
 283         return;
 284     }
 285
 286     echo = (icmpEchoData *) pkt;
 287
 288     preply.opcode = echo->opcode;
 289
 290     struct timeval tv;
 291     memcpy(&tv, &echo->tv, sizeof(struct timeval));
 292     preply.rtt = tvSubMsec(tv, now);
 293
 294     /*
 295      * FIXME INET6: Without access to the IPv6-Hops header we must rely on the total RTT
 296      *      and could caculate the hops from that, but it produces some weird value mappings using ipHops
 297      *  for now everything is 1 v6 hop away with variant RTT
 298      * WANT:    preply.hops = ip->ip6_hops; // ipHops(ip->ip_hops);
 299      */
 300     preply.hops = 1;
 301
 302     preply.psize = n - /* sizeof(ip6_hdr) - */ sizeof(icmp6_hdr) - (sizeof(icmpEchoData) - MAX_PKT6_SZ);
 303
 304     /* Ensure the response packet has safe payload size */
 305     if ( preply.psize > (unsigned short) MAX_PKT6_SZ) {
 306         preply.psize = MAX_PKT6_SZ;
 307     } else if ( preply.psize < (unsigned short)0) {
 308         preply.psize = 0;
 309     }
 310
 311     Log(preply.from,
 312         icmp6header->icmp6_type,
 313         ( icmp6header->icmp6_type&0x80 ? icmp6HighPktStr[(int)(icmp6header->icmp6_type&0x7f)] : icmp6LowPktStr[(int)(icmp6header->icmp6_type&0x7f)] ),
 314         preply.rtt,
 315         preply.hops);
 316
 317     /* send results of the lookup back to squid.*/
 318     control.SendResult(preply, (sizeof(pingerReplyData) - PINGER_PAYLOAD_SZ + preply.psize) );
 319     Ip::Address::FreeAddrInfo(from);
 320 }
 321
 322 #endif /* USE_ICMP */